A 46 year old white woman presented to her local casualty department. She had been experiencing vaginal bleeding for 10 days, and the bleeding had become particularly heavy in the past three days. She had also felt generally unwell for around a week with malaise, fatigue, headaches, anorexia, and vomiting.

She and her partner had been trying to conceive. Her last menstrual period had been 10 weeks ago and she had recently tested positive with a urinary (β human chorionic gonadotrophin) pregnancy testing kit. She had three children from a previous partner. Two of these …

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